A single-letter change in the genetic code is enough to generate blond hair in humans, in dramatic contrast to our dark-haired ancestors. A new analysis by Howard Hughes Medical Institute (HHMI) scientists has pinpointed that change, which is common in the genomes of Northern Europeans, and shown how it fine-tunes the regulation of an essential gene. "This particular genetic variation in humans is associated with blond hair, but it isn't associated with eye color or other pigmentation traits," says David Kingsley, an HHMI investigator at Stanford University who led the ...

Researchers at the University of California, San Diego School of Medicine have erased and reactivated memories in rats, profoundly altering the animals' reaction to past events. The study, published in the June 1 advanced online issue of the journal Nature, is the first to show the ability to selectively remove a memory and predictably reactivate it by stimulating nerves in the brain at frequencies that are known to weaken and strengthen the connections between nerve cells, called synapses. "We can form a memory, erase that memory and we can reactivate it, at will, ...

DURHAM, N.C. – A collaborative effort between Duke Medicine researchers and neurosurgeons and scientists in China has produced new genetic insights into a rare and deadly form of childhood and young adult brain cancer called brainstem glioma. The researchers identified a genetic mutation in the tumor cells that plays a role in both the growth and the death of a cell. Additionally, the mutation to the newly identified gene may also contribute to the tumor's resistance to radiation. The findings, published online in the journal Nature Genetics on June 1, 2014, provide ...

Laser beams 60,000 billion times more powerful than a laser pointer have been used to recreate scaled supernova explosions in the laboratory as a way of investigating one of the most energetic events in the Universe. Supernova explosions, triggered when the fuel within a star reignites or its core collapses, launch a detonation shock wave that sweeps through a few light years of space from the exploding star in just a few hundred years. But not all such explosions are alike and some, such as Cassiopeia A, show puzzling irregular shapes made of knots and twists. To investigate ...

Around a quarter of smokers who carry a defect in the BRCA2 gene will develop lung cancer at some point in their lifetime, a large-scale, international study reveals. Scientists announce a previously unknown link between lung cancer and a particular BRCA2 defect, occurring in around 2 per cent of the population, in research published in Nature Genetics today (Sunday). The defect in BRCA2 - best known for its role in breast cancer - increases the risk of developing lung cancer by about 1.8 times. Smokers as a group have a high lifetime risk of around 13 per cent (16 ...

Using a flash of light, scientists have inactivated and then reactivated a memory in genetically engineered rats. The study, supported by the National Institutes of Health, is the first cause-and-effect evidence that strengthened connections between neurons are the stuff of memory. "Our results add to mounting evidence that the brain represents a memory by forming assemblies of neurons with strengthened connections, or synapses, explained Roberto Malinow, M.D., Ph.D., of the University of California, San Diego (UCSD), a grantee of the NIH's National Institute of Mental ...

HOUSTON – (June 1, 2014) – Baylor College of Medicine scientists defined a previously unrecognized genetic cause for two types of birth defects found in newborn boys, described in a report published today in the journal Nature Medicine. "Cryptorchidism and hypospadias are among the most common birth defects but the causes are usually unknown," said Dr. Dolores Lamb, director of the Center for Reproductive Medicine at Baylor, professor and vice chair for research of urology and molecular and cellular biology at Baylor and lead author of the report. Cryptorchidism is ...

HOUSTON -- (June 1, 2014) -- The first preclinical study of a new Rice University-developed anti-cancer technology found that a novel combination of existing clinical treatments can instantaneously detect and kill only cancer cells -- often by blowing them apart -- without harming surrounding normal organs. The research, which is available online this week Nature Medicine, reports that Rice's "quadrapeutics" technology was 17 times more efficient than conventional chemoradiation therapy against aggressive, drug-resistant head and neck tumors. The work was conducted by ...

Researchers from the Spanish National Research Council (CSIC) have developed a software based on the discovery of some algorithms that enable the identification of each individual, therefore allowing their tracking within the group. Thus, the door opens to the quantitative study of the rules of social interaction for many species. The work has been published in the Nature Methods journal. Animals that move in groups make decisions considering what other members of their community do. To find out the rules of these interactions, researchers record monitoring videos through ...

Writing in Nature Physics, a large international team led by Dr Artem Mishchenko and Sir Andre Geim from The University of Manchester shows that the electronic properties of graphene change dramatically if graphene is placed on top of boron nitride, also known as 'white graphite'. One of the major challenges for using graphene in electronics applications is the absence of a band gap, which basically means that graphene's electrical conductivity cannot be switched off completely. Whatever researchers tried to do with the material so far, it remained highly electrically ...

The combined action of two enzymes, Srs2 and Exo1, prevents and repairs common genetic mutations in growing yeast cells, according to a new study led by scientists at NYU Langone Medical Center. Because such mechanisms are generally conserved throughout evolution, at least in part, researchers say the findings suggest that a similar DNA repair kit may exist in humans and could serve as a target for controlling some cancers and treating a rare, enzyme-linked genetic disorder called Aicardi-Goutieres syndrome. The syndrome, an often fatal neurological condition, is found ...

PITTSBURGH—University of Pittsburgh researchers have become the first to detect a fundamental particle of light-matter interaction in metals, the exciton. The team will publish its work online June 1 in Nature Physics. Mankind has used reflection of light from a metal mirror on a daily basis for millennia, but the quantum mechanical magic behind this familiar phenomenon is only now being uncovered. Physicists describe physical phenomena in terms of interactions between fields and particles, says lead author Hrvoje Petek, Pitt's Richard King Mellon Professor in the Department ...

STANFORD, Calif. — A molecule critical to stem cell function plays a major role in determining human hair color, according to a study from the Stanford University School of Medicine. The study describes for the first time the molecular basis for one of our most noticeable traits. It also outlines how tiny DNA changes can reverberate through our genome in ways that may affect evolution, migration and even human history. "We've been trying to track down the genetic and molecular basis of naturally occurring traits — such as hair and skin pigmentation — in fish and humans ...

VIDEO: This video simulation shows how a laser that illuminates a small carbon rod launches a complex flow, consisting of supersonic shocks and turbulent flow. When the grid is present, turbulence... Click here for more information. Astrophysicists have established that cosmic turbulence could have amplified magnetic fields to the strengths observed in interstellar space. "Magnetic fields are ubiquitous in the universe," said Don Lamb, the Robert A. Millikan Distinguished ...

A UCLA research team has discovered a new hormone called erythroferrone, which regulates the iron supply needed for red blood-cell production. Iron is an essential functional component of hemoglobin, the molecule that transports oxygen throughout the body. Using a mouse model, researchers found that erythroferrone is made by red blood-cell progenitors in the bone marrow in order to match iron supply with the demands of red blood-cell production. Erythroferrone is greatly increased when red blood-cell production is stimulated, such as after bleeding or in response to anemia. The ...

Twenty years after the hormone leptin was found to regulate metabolism, appetite, and weight through brain cells called neurons, Yale School of Medicine researchers have found that the hormone also acts on other types of cells to control appetite. Published in the June 1 issue of Nature Neuroscience, the findings could lead to development of treatments for metabolic disorders such as obesity and diabetes. "Up until now, the scientific community thought that leptin acts exclusively in neurons to modulate behavior and body weight," said senior author Tamas Horvath, the ...

CHICAGO — Molecular sequencing could identify ovarian cancer patients who are most likely to benefit from treatment with bevacizumab (Avastin), a Mayo Clinic-led study has found. Results of the research were presented today at the 2014 American Society of Clinical Oncology Annual Meeting. The addition of bevacizumab to standard therapy extended progression-free survival more for ovarian cancer patients with molecular subtypes labeled as "proliferative" or "mesenchymal" compared to those with subtypes labeled as "immunoreactive" or "differentiated," says Sean Dowdy, M.D., ...

As targeted therapies become more available, increasing opportunity exists to match treatments to the genetics of a specific cancer. But in order to make this match, oncologists have to know these genetics. This requires molecular testing of patient samples. An education session presented today at the American Society for Clinical Oncology (ASCO) Annual Meeting 2014 details the challenges in this process and makes recommendations that oncologists can use to ensure their patients' samples are properly tested, helping to pair patients with the best possible treatments. "The ...

CHICAGO — A chemotherapy regimen consisting of procarbazine, CCNU, and vincristine (PCV) administered following radiation therapy improved progression-free survival and overall survival in adults with low-grade gliomas, a form of brain cancer, when compared to radiation therapy alone. The findings were part of the results of a Phase III clinical trial presented today at the 2014 American Society of Clinical Oncology Annual Meeting by the study's primary author Jan Buckner, M.D., deputy director, Cancer Practice, at Mayo Clinic Cancer Center. "On average, patients who ...

ATLANTA – June 1, 2014 – The number of cancer survivors in the United States, currently estimated to be 14.5 million, will grow to almost 19 million by 2024, according to an updated report by the American Cancer Society. The second edition of Cancer Treatment & Survivorship Facts & Figures, 2014-2015 and an accompanying journal article published in CA: A Cancer Journal for Clinicians find that even though cancer incidence rates have been decreasing for ten years, the number of cancer survivors is growing. This is the result of increases in cancer diagnoses driven by the ...

Forget about positioning giant mirrors in space to reduce the amount of sunlight being trapped in the earth's atmosphere or seeding clouds to reduce the amount of light entering earth's atmosphere. Those approaches to climate engineering aren't likely to be effective or practical in slowing global warming. A new report by professors from UCLA and five other universities concludes that there's no way around it: We have to cut down the amount of carbon being released into the atmosphere. The interdisciplinary team looked at a range of possible approaches to dissipating ...

CHICAGO — June 1, 2014 — In the largest clinical trial testing the effectiveness of one versus two drugs to treat HER2-positive breast cancer, lapatinib (Tykerb) did not add benefit to the standard trastuzumab (Herceptin) adjuvant therapy, researchers report at the 50th annual meeting of the American Society of Clinical Oncology (ASCO). MULTIMEDIA ALERT: Video and audio are available for download on the Mayo Clinic News Network. Results of the phase III clinical trial, ALTTO (Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization study), demonstrated that adding ...

An Emeritus Professor of medical ethics at Imperial College London will deliver a presentation at this year's Euroanaesthesia meeting titled 'Escalating care for the comorbid elderly-where do we stop?". Raanan Gillon, who is President of the UK's Institute of Medical Ethics, will argue that a patient's age should not in itself be considered an ethically relevant criterion for deciding 'where to stop'. Acknowledging that there is a morally plausible counter-argument – known in the UK as 'the fair innings argument'- according to which scarce life prolonging resources should ...

A systematic review and meta-analysis of hospital data worldwide, presented as this year's Euroanaesthesia meeting in Stockholm, adds further evidence that patients admitted to hospital at weekends have higher mortality than those admitted on weekdays. The study is by Dr Hiroshi Hoshijima, Tohoku University, Sendai, Japan, and colleagues. The analysis included 72 studies from various world regions, covering 55,053,719 participants. The authors found that weekend admission was associated with increased morality of between 15% and 17% depending on the statistical technique ...

New research presented at this year's Euroanaesthesia show that on weekends, in the afternoons and in February are the times when the risk of death following surgery is the highest. The research is by Dr Felix Kork and Professor Claudia Spies, Charité - University Medicine Berlin, Germany and colleagues. Hospital mortality is subject to day-night, weekly and seasonal variability. This has been shown for various populations, settings, and in different regions of the world. However, a cyclic influence on hospital mortality has not been shown in patients after surgery. ...